Platen-lock for type-writing machines.



I. RBB.

PLATBN LOOK POR TYPE WRTIHG MAEXNES.

` APPLICATION FILED SEPT 29, 190'9.

l0, WM.

2?' team@ llllil WITNESSES @LLM/AT A TTORNE Y.

L GRBB.

- LTEN LOCK FOB TYPE WR'lNG HAGHNES.

WITNESSES APPLIUATIOIT ELED SEPT. 29, 1909.

` Famenne@ Jan. mm1.

2 SHEETS-SHEET 2.

IN VEN TOR. I

regular structure and which, t-hrough the in IRA N. CRABB,OFiEN-AGLEWOOD., COLORADO.

PLATEN-LOCK FOR TYPE-WRITING MACHINES.

Specification of Letters Patent.

Patented Jan. 1o, 1911.

Application filed September 2.91909- Serial No. 520,176.

To all whom it' may concern:

Be it known that I, IRA N. CRABB, a citizen of the United States ofAmerica, residing at Englewood, in the county of Arapahoe and State ofColorado, have invented certain new and useful Improvements inPlaten-Locks for Type-Writing Machines, of which the following is aspecification.

My invention relates to attachments for type-writing machines and moreparticularly to sto devices by means of which the platen of tie machinemay be arrested at any one of a plurality of predetermined points in itsrotation.

The object of my invention is to provide a device of simple constructionwhich may be readily attached to ,an existing typewriter machine'without material change in its strumentality of an adjustable membermoving coincidently with the platen, w1ll arrest movement of the latter,and in consequence of the sheet ofpap'er carried thereby, atl any(selected point and for the iirpose of 4'preventing writing beyond atance from the lower edge of said sheet.

My invention, by the accomplishment of the above object, obviates thenecessity of raising the platen-carriage to ascertain the position ofthe paper relative to the line p'f Writing, insures uniformity in theappear ance of the various pages ,of ,a manuscriplt, i t e reventswriting on 4che'platen beyond ower edge of the paper, and in general,saves time, labor Aand expense by automatically arresting the movementoftthe paper before its lower edge has reached the point at which thetype is lbrought-in contact therewith. i h The above and other objectswhich will hereinafter mnem,

drawings i; the various views of whichlike parts are similarlydesignated and in which- 4 Figure 1, represents, an end view of theupper portion of an Underwood typewriting machine With myqattachment inits operative positie a. -Fig. 2, a lan view thereof, Fig. 3, anenlarged, sectional view of the spring-controlled winding spoolcomprised in my4 invention, and adjacent parts, Fig. 4,anel'ilargedwiewofthe end of the device eterminate dis- 'lj l attainedby the mechanisnlillustrated in the accompanying opposite to that shownin the preceding figure, and adjacent parts of the typewrit- Vingmachine, Fig. 5, a perspective view of the flexible band employed in theform shown in Fig.. 1, and of the stop button associated therewith, andFig. 6, an enlarged.

longitudinal sectionv through a portion of said band and through saidbutton.

' Referring to the drawings by numerical characters, let the numeral 2designate the stationary frame of a typewriting machine, 3the-reciprocating carriage, 4 the platen revolubly mounted upon thelatter, 5 the platen-shaft and 6 the knob at one extremity thereof, bymeans of which the platen may be manually rotated.

My attachment as shown in the drawings,

comprises 'an angularly bent bar 8 one end of which lstpivotally securedby means of a screw 7 upon the outer surface of the endbar 3a of thecarriage 3, and which, at its opposite extremity, is loosely supportedfupon the upper surface'of the same. The

bar 8.V is, to this end, formed with a laterally projecting lip 8a whichnormally rests .upon the upper surface of the carriage and this lip isengaged by the free extremity of a leaf spring 9 whose opposite end isfixed upon the carriage and which servesto resili- V-ently maintain thebar in its normal position', A lever 10 fulcrumed at v12 upon thecarrier 8, beneath the free extremity of the bar 8, isemployed to movethe latter about its pivot vagainst the action of the s ring 9 for apurpose hereinafter to be described and ity consists to this end of anarm 10a which engages the lower edge of the bar 8 and an larm 10 which,`projecting beyond the carriage is enlarged at its extremity to bepressed' by vthethunib'of the operator.

Revolu ly mounted upon-the bar 8 and, 95

preferably at a point perpendicularly above the axis of the platen shaft5, is a Windingspool 13, the inner fiange 13a of which is formed withperipheral teeth which, normally, mesh with a gear wheel 14 fixed onlthe platen shaft. A second spool 15 is rotatably mounted upon the shankofthe before mentioned screw 7- which projects-beyond the outer surfaceof the bar 8, and the barrel 15 of this spool is made hollow for thereception of a coiled spring 16 the extremities tions 19. .c

'the band, through the action of a spring 21 the last line,predetermined by the operator, v

of -which are respectively secured to the j screw 7 and to the barreland which, when j wound upt'ends to revolve the-latter in the directionof the arrow in Fig. 1'.

, A flexible band 17., the terminal portions of which wind respectivelyupon the spools 13 and 15 to which its extremities are attached,projects through a correspondingly formed slot in a stop-lug 18 whichprojects from the bar 8 intermediate of the two spools and the said bandis formed with a series of perforations 19 which are numberedconsecutively as shown in Figs. 2 and 5.

A button 20 which is slidably supported upon the upper surface of theband 17 is provided with a'pivoted plate 22 Iadapted to clampinglyengage the under surface of and this plate has an upturned detent 23which'when the button is in its adjusted position, projects into one ofthe perfora described the construction of my invention, its operationwill be readily understood. Premising that the distances between thepcrforations 19 of the band 1,8 are proportional to the distancesbetween the lines of writing on the paper carried by the platen or withother words to thelengths of the intermittent rotatory movements of thelatter, and that the first one (l) of the consecutive'l numbers isadjacent 'the extreme end of the band secured to the spool 13, theoperator having determined the number of lines to be written on thesheet, adjusts the appliance in the following manner: Having loosenedthe button 2O from the fiexible band, the former is held in engagementwith the stop-lug 18 and the platen'is rotated by means of the knob 6for the purpose of wind` ing the band upon the spool 13. This operationis continued until the perforation 19, corresponding, numerically, withthe last line to be written on the sheet, is below the button so as toreceive the detent 23 on the clamp 22 when th'e latter is brought inengagement with the under surface of the band to firmly secure thebutton in position. The free end of the bar 8 is now raised by means ofthe thumb lever 10, to disengage the toothed flange 181 of the spool 13,from the gearwheel 14:, for the purpose of rewinding the tape upon thespool 15, which isautomatically accomplished by action of the spring 16which was wound up during the rotatory movement of the platen. When theentire band is thus unwound from the spool l5, the device is returned toits original position after which the sheet of paper is inserted in themachine. As the movement of the band is coincident with the intermittentmovement of the platen, the button 20 will engage the stop 18 at thesame time that Having thus is written on the sheet, and it will byreason of said engagement, arrest the movement of the band and, inconsequence, that of the platen and the sheet of paper. carried thereon.

I wish it understood that while I have shown and described the inventionin the best form now known to me, variations in the form and arrangementof the parts, necessary to render the device suitable for use on themany dierent writing machines at present on lthe market, may be resortedto Without departing from the spirit of the invention.

What I claim and Letters Patent is 1. In a typewriting machine, thecombination With the rotative platen, of a rotative spool cooperativetherewith, a flexible band arranged to be wound on said spool during itsmovement in one direction, a spring actuated spool connected with theopposite end (if said band and adapted to move it in the oppositedirection, a stop member on said band, and a means for arresting themovement of said member at a predetermined point.

2. In a typewriting machine, the combi-- nation with the carriage andthe platen rotatably mounted thereon, of a bar movably supported onsaid-carriage, a winding spool on said bar, means for transmitting themovement of the platen to said spool, a flexible band arranged to bewound on said spool during its movement 'in one direction, a sto said arfor arresting the movement of said member at a predetermined point.

3.,In a typewriting machine, the coni, nation with the carriage and theplaten ref` tatably mounted thereon, of a bar movably supported on saidcarriage, a winding spool on said bar, means for transmitting themovement of the platen to said spool, a ieX- ible band arranged to bewound on said spool during its movement in one direction, a springactuated spool on said bar connected with the opposite end of the bandand adapted to move it in the opposite dif rection, a stop member onsaid band, and a means on said bar for arresting the movement` of saidImember at a determinate point.

4. In a typewriting machine the combi nation with the -carriage and thelaten, rotatably mounted thereon, of an e ement pivotally mounted at oneof its ends to said carriage, its opposite end being normally heldagainst movement beyond a predetermined point a winding spool on saidclefl ment, gear wheels respectively on said spool and on the platen,which are inoperative engagement while the bar is in its normalposition, a liexible band arranged to be wound on said spool during itsmovement desire to secure by member on said band, and la means on lio inone direction, a spring-atugted spool on said bar connected With theopposite end of the band and adapted to move it in the o ppositedirection, a stop member on said band, and a means on said bar forarresting the movement .of said member at n determinate point. f

In testimony whereofA I have affixed my signature 1n presence of twoWitnesses,

111A N. CRABB.

Witnesses:

`Gr. J. ROLLANDET, I M. L. GEARY. u

